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A132023 Decimal expansion of Product{k>=0, 1-1/(2*7^k)}. 2
4, 5, 8, 7, 6, 6, 7, 2, 6, 6, 9, 9, 7, 6, 8, 9, 8, 5, 0, 2, 0, 0, 0, 5, 1, 5, 3, 3, 6, 9, 7, 4, 3, 7, 2, 1, 7, 8, 2, 5, 4, 6, 6, 8, 8, 7, 1, 4, 7, 3, 1, 8, 7, 0, 0, 7, 8, 2, 4, 4, 0, 1, 3, 8, 5, 0, 6, 9, 9, 7, 4, 4, 0, 3, 2, 6, 5, 9, 3, 0, 3, 6, 5, 2, 3, 7, 8, 1, 7, 1, 0, 9, 0, 4, 0, 5, 8, 4, 7, 5, 9, 8, 2 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..102.

FORMULA

lim inf product{0<=k<=floor(log_7(n)), floor(n/7^k)*7^k/n} for n-->oo.

lim inf A132031(n)/n^(1+floor(log_7(n)))*7^(1/2*(1+floor(log_7(n)))*floor(log_7(n))) for n-->oo.

lim inf A132031(n)/n^(1+floor(log_7(n)))*7^A000217(floor(log_7(n))) for n-->oo.

1/2*exp(-sum{n>0, 7^(-n)*sum{k|n, 1/(k*2^k))}}).

lim inf A132031(n)/A132031(n+1)=0.4587667266997689850200... for n-->oo.

EXAMPLE

0.4587667266997689850200...

MATHEMATICA

digits = 103; NProduct[1-1/(2*7^k), {k, 0, Infinity}, NProductFactors -> 200, WorkingPrecision -> digits+5] // N[#, digits+5]& // RealDigits[#, 10, digits]& // First (* Jean-Fran├žois Alcover, Feb 18 2014 *)

CROSSREFS

Cf. A048651, A098844, A067080, A132019, A132026, A132031, A132035, A000217.

Sequence in context: A296495 A020804 A021222 * A107758 A104883 A154885

Adjacent sequences:  A132020 A132021 A132022 * A132024 A132025 A132026

KEYWORD

nonn,cons

AUTHOR

Hieronymus Fischer, Aug 14 2007

STATUS

approved

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Last modified January 21 05:39 EST 2020. Contains 331104 sequences. (Running on oeis4.)